Spinning solution



Patented Apr. 24, 1934 UNITED STATES PATENT OFFICE SPINNING SOLUTION tion of Delaware No Drawing. Application December 20, 1930, Serial No. 503,759

8 Claims.

This invention relates to the production of regenerated cellulose structures, such as sheets, films, thread, filaments, hollow bodies, including caps, bands, sausage casings and the like, having substantially uniform characteristics including a low luster. More particularly, it relates to a method of securing regularity in the formation of regenerated cellulose structures and the cellulosic solutions employed in said method.

10 Prior to this invention, viscose artificial thread having a low luster was produced by incorporating into the viscose solution, previous to the spinning, low luster-inducing materials which were either liquids, such as mineral oil, or solids,

such as finely divided pigments or pigment-like bodies or mixtures of both liquids and solids of the previously mentioned type, spinning such a viscose solution and subsequently finishing the thread in the usual and well known manner.

The degree of luster is a function of the amount and particle size of the low luster-inducing material present in the thread as well as the dinerences in the refractive indices of said material and the substance constituting the major proportion of the thread. Hence, by varying one and/or more of the factors, a product having a luster equal to, higher or lower than natural silk could be produced as desired.

It is apparent that the physical characteristics of the product as well as the constitution thereof should be substantially uniform. In the case of artificial thread, it is also essential that it be continuous as to its mass material and that the low luster-inducing agent resist removal by 5 washing, dyeing and other treatments to which the thread may be subjected in finishing or in actual use. To achieve these desiderata it is necessary to uniformly distribute and disperse the low luster-inducing agent and this was obtained to a certain degree prior to this invention by dispersing the low luster-inducing agent in the' presence of dispersing agents, such as soaps, oils, alkylated naphthalene sulphonic acids or the like.

The previously described procedure has several disadvantages. Certain low luster-inducing agents are more difficult to incorporate uniformly in the viscose solution than others or, having been incorporated, are comparatively diflicult to maintain in that condition. For example, in the viscose process it was usual to add the low luster-inducing agents to the viscose solution at the stage when the cellulose xanthate was being dissolved in a caustic soda solution. Commonly,

the addition was made before the viscose solution was subjected to the ripening period and/or before it was evacuated to remove the air. There was, therefore, a long interval of time between the time the low luster-inducing agent was dispersed in the viscose solution and. the time when the regenerated cellulosestructure was formed in the coagulating bath. During this long interval of time the low luster-inducing agent did not remain uniformly dispersed throughout the viscose solution. It had a tendency to cream, i. e. separate out from the solution. As a result and particularly when the low luster-inducing material was non-celiulosic (in the sense of not being capable of forming a thread by itself), spinning was necessarily more critical and inter- 7 rupted spinning was common. Moreover, the regenerated cellulose structures, such as threads, that were produced did not have a uniform degree of luster or uniform and high physical qualties.

Stated in somewhat different terms, I have found that, when a low luster-inducing agent, such as mineral oil, is dispersed in a cellulosic solution, such as viscose, by means of a dispersing agent, such as a soap, a sulphonated oil or an alkylated naphthalene sulphonic acid, the interfacial tension between the oil and viscose is comparatively high and creaming takes place after some time and to such an extent that the uniform distribution of the low luster-inducing agent in the viscose is disturbed. As a consequence, spinning is bad and the physical qualities of the thread produced is so low and so nonuniform as to be a matter of serious concern. Moreover, the securing of threads of uniform low luster becomes difficult.

I have also found, and this constitutes a part of this invention, that this difliculty may be greatly reduced and even substantially eliminated by the introduction of a small amount of an agent which I usually call, for want of a better term, a creaming preventative. By creaming preventative is meant a material which, when associated with a system such as one comprising viscose, mineral oil and a dispersing agent, 0 will maintain uniform dispersion and will produce good and uniform spinning, so that threads of uniform low luster, uniform physical characteristics and good physical strength will be produced.

Specifically, I'have found that, if I add to a low luster-inducing liquid, such as a mineral oil, which is to be dispersed in a. cellulosic solution, such as viscose, by means of a dispersing agent, a small amount of a substance which dis- 9 solves in or is miscible with the mineral oil and which is preferably though not necessarily miscible with the dispersing agent and which also preferably lowers the interfacial tension be- 5 tween the mineral oil and the viscose, a viscose solution is established which spins well and does not cream in the usual steps of making and spinning the viscose solution with the result that the thread or other regenerated cellulose structure produced is much more uniform in proper'- ties. In other words, I have found that by incorporating a creaming preventative in a cellulosic solution of the type previously described, regularity in spinning in the case of thread or regularity in the formation of regenerated cellulose structures will be obtained.

It is therefore an object of this invention to provide a method wherein regularity in spinning in the case of thread or regularity in the formation of the regenerated cellulose structure is obtained.

Another object of this invention is to provide a cellulosic solution from which sheets, threads, hollow bodies, such as caps, sausage casings and bands, may be produced with marked and improved regularity, said products having substantially uniform properties possessing a brilliance equal to, higher or lower than natural silk.

Another object of this invention is to provide a solution from which regenerated cellulcs structures having a degree of luster equal to, higher or lower than natural silk may be obtained, said solution exhibiting no tendency to cream, with the result that regularity in the formation of the regenerated cellulose structures is obtained.

A further object of this invention is to provide a cellulosic solution, from which regenerated cellulose structures are obtained, containing, for example, viscose, a liquid low lusterinducing agent, such as an oil, a dispersing agent, and an agent to prevent creaming of said solution.

A still further object of this invention is to provide a cellulosic spinning solution contaning a low luster-inducing liquid, such as mineral oil, a dispersing agent, and an agent which prevents creaming thereof, said agent being preferably miscible with said mineral oil and/or reducing the interfacial tension between the viscose and the mineral oil and/or miscible with the dispersing agent.

A specific object of this invention is to prepare a viscose solution to be used in the production of regenerated cellulose structures containing mineral oil, a dispersing agent and also an agent which prevents creaming of said solution, said agent being present in small amounts and preferably compatible with the mineral oil, and/or reducing the interfacial tension between the mineral oil and the viscose.

Other objects will appear from the following description and appended claims.

As is apparent from the foregoing, one of the esssential features of this invention is to provide a method wherein regularity in spinning in the case of the production of thread or regularity in the formation of regenerated cellulose structures is obtained, particularly when a cellulosic solution, such as a viscose solution containing a low luster-inducing agent, such as a mineral oil, dispersed therein by means of a dispersing agent, such as Monopole oil, is employed. This result is obtained by adding to a cellulosic solution of the type mentioned an agent which prevents creaming and maintains the dispersion in a substantially uniform state. In addition to securing regularity in spinning in the case of threads or regularity in the formation of regenerated structures, products of substantially uniform characteristics and good physical strength, as well as uniform low luster, will be produced.

In the preferred form the creaming preventative employed in accordance with the principles of this invention is soluble or miscible in or otherwise compatible with the mineral oil and is also preferably, but not necessarily, miscible with the dispersing agent. Also, it preferably lowers the interfacial tension between the mineral oil and the viscose.

In order to more clearly explain the invention, the following example is given:

Example-20 pounds of a mineral oil are emulsified in 22 pounds of water using 250 cc. of Monopole oil by adding the mineral oil with agitation to the mixture of the water and Monopole oil. The emulsion so formed is added with agitation to 5,000 pounds of viscose solution of the normal type and containing approximately 7% more or less of cellulose.

Such a viscose solution will, during the period starting with the introduction of the emulsion and ending with the spinning operation, have a tendency to cream which will cause bad spinning, poor quality in the resulting thread and a nonuniform luster. If, however, a material, such as terpineol, or pine oil, preferably in the ratio of 1 part to 5 to 10 parts by weight of the mineral oil, is added, the resulting viscose solution will be found to remain stable for days and show no tendency to cream with the consequent improvement of regularity in spinning, quality, and uniformity of luster.

In the foregoing examples, the thread produced from the cellulosic solution containing the creaming preventative is of the solid variety and in this respect is similar to the thread pro-"- duced from the cellulosicsolution fr ee'from the cr ming preventative. 1

Though pine oil or terpineol may be incorporated in the solution at any stage in thepreparation thereof, I prefer to incorporate it in the mineral oil before the latter is emulsified in the water.

While pine oil and terpineol are specifically mentioned and are preferred, there are numerous other materials which function similarly thereto and produce similar results, though perhaps not as good. The criterion seems to be that the creaming preventative should be miscible or soluble in the low luster-inducing agent and should also, preferably, be miscible with the dispersing agent. Also, it should preferably lower the interfacial tension between the low luster-inducing agent and the viscose.

The creaming preventative is practically insoluble in the viscose. It may or may not contribute to the final luster of the product. It may remain in the thread as a material having a different index of refraction from the regenerated cellulose or it may be completely or partly dissipated or removed during or subsequent to spinning.

It is immaterial whether or not the creaming preventative lowers or reduces the surface tension of the low luster-inducing agent. In fact, it may even raise the surface tension of the low luster-inducing agent without producing any unsatisfactory results. Similarly, it may or may not affect the surface tension of the viscose.

Among the other materials which have produced satisfactory results, though not as good as pine oil and terpineol may be mentioned benzene,

toluene, xylene, chlorbenzene, dichlorbenzene, tetralene, turpentine, gasoline, hexalin, hexane, and carbon tetrachloride.

As apparent from the foregoing example, the quantity of creaming preventative employed is insuflicient to effect the solidity in the final regenerated structure.

' In the foregoing, prevention of creaming normally present when mineral oil is used was de scribed, but it is clear that the principles of this invention are equally applicable with other materials which show a tendency to cream or separate when emulsified in viscose or other cellulosic solutions. Some of such materials are similar in nature to mineral oil in that they are high boiling petroleum bodies. For example, petroleum jelly, parafiln oil and similar materials exhibit a tendency to cream which can be overcome by utilizing the principles of this invention. It is also to be understood that the principles of this invention are applicable to materials other than those derived from petroleum.

It is also to be understod that the principles of this invention may be utilized in the production of solutions containing mineral oils and/or pigments, and this invention is intendedto embrace such procedures.

Though the specific example has been described in connection with the production of artificial thread of the solid variety, it is to be understood that the teachings of this invention are equally applicable in the production of other products of the solid variety of regenerated cellulose, such as sheets, films, hollow bodies, such as caps, bands and sausage casings, from viscose, cuprammonium cellulose, and the like.

Since it is obvious that various changes and modifications may be made in the invention above set forth without departing from the spirit of it, the invention is not restricted to the specific details described except as defined in the appended claims.

I claim:

1. In a method of improving regularity in the formation ofregenerated cellulose structures of the solid variety from a cellulosic solution containing a low luster-inducing agent and a dispersing agent, the step of incorporating in said solution a creaming preventative in the proportion of 1 part thereof to 5-10 parts by weight of the low luster-inducing agent prior to coagulation and regeneration.

2. In a method of improving regularity in the formation of regenerated cellulose structures of the solid variety from a viscose solution containing a mineral oil and a dispersing agent, the step of incorporating in said solution a creaming preventative in the proportion of 1 part thereof to 5-10 parts by weight of the said mineral oil prior to coagulation andregeneration.

3. In a. method of improving regularity in the formation of regenerated cellulose structures of the solid variety from a viscose solution containing a mineral oil and a dispersing agent, the step of incorporating in said solution pine oil in the proportion of 1 part thereof to 5-10 parts by weight of the said mineral oil prior to coagulation and regeneration.

4. In a method of improving regularity in the formation of regenerated cellulose structures of the solid variety from a viscose solution containing mineraloil and a dispersing agent, the step of incorporating in said solution terpineol in the proportion of 1 part thereof to 5-10 parts by weight of the said mineral oil prior to coagulation and regeneration.

5. In a method of improving regularity in the formation of regenerated cellulose structures of the solid variety,the steps which comprise adding 1 part of a creaming preventative to 5-10 parts by weight of a low luster-inducing agent, dispersing the low luster-inducing agent, and incorporating said dispersion in a cellulosic solution.

6. In a method of improving regularity in the formaton of regenerated cellulose structures of the solid variety, the steps which comprise mixing 5-10 parts by weight of a mineral oil with 1 part of a creaming preventative, dispersing said oil, and incorporating the dispersion in a cellulosic solution. I

7. In a method of improving regularity in the formation of regenerated cellulose structures of the solid variety, the steps which comprise mixing 5-10 parts by weight of a mineral oil with 1 part of pine oil, dispersing said oil, and incorporating the dispersion in a cellulosic solution.

8. In a method of improving regularity in the formation of regenerated cellulose structures of the solid variety, the steps which comprise mixing 5-10 parts by weight of a mineral oil with 1 part of terpineol, dispersing said 011, and incorporating the dispersion in a cellulosic solution. 

